Tensegrity-Inspired Polymer Films: Progressive Bending Stiffness through Multipolymeric Patterning

Materials with J-shaped stress-strain behavior under uniaxial stretching, where strength increases as deformation progresses, have been developed through various materials designs. On the other hand, polymer materials that progressively stiffen under bending remain unrealized. To address this gap, this study drew inspiration from membrane tensegrity structures, which achieve structural stability by balancing compressive forces in rods and tensile forces in membrane. Notably, some of these structures exhibit increased stiffness under bending. Using a multipolymer patterning technique, we developed a polymer film exhibiting membrane tensegrity-like properties that stiffens under bending. This effect results from membrane tension generated by rod protrusions and an increase in second moment of area at regions with maximum curvature.